Parade

Ask Marilyn: Are They Equal? Or Not?

David Robinson of Burlington, Massachusetts, writes:

Marilyn: Recently I was performing a task that had two possible orientations. Think of left and right or up and down, binary. Either orientation was possible, but only one was correct. I did not have enough information at the time to determine the correct orientation, and there was no way for me to get additional information. I was going to make a number of these. The two ways I could make the set were: a) all in one direction; or b) half in one direction and half in the other direction. This meant I had either a 50 percent chance of being 100 percent correct, or a 100 percent chance of being 50 percent correct. Do you feel one choice is better than the other? Marilyn responds:

Yes, but it's dependent on the context. You had some information when you started, so you would use whatever you knew. For example, was making the full complement of correct items critical to the success of whatever they would be used for? If so, choosing (a) may be better. Choosing (b) would always cause failure. Another example: Were you in a rush to complete the task? If so, choosing (b) may be better. At least half of the items would be ready on time. The list goes on and on.